Abstract: :
Purpose: To assess feasibility and biocompatibility of a lamellar,non–perforating synthetic cornea implanted in rabbit eyesfollowing a corneal injury.Methods: Corneal vascularisation and scarring was induced inthe right eye of 15 rabbits by application of 1–heptanoland complete surgical removal of the limbus. Implantation ofan sDSC (7mm diameter, 450µm thick optical zone, 100µmthick outer flange) was performed after 45 ± 5 days.The KPro’s were implanted with their central optic partpositioned on a completely exposed Descemet’s membrane(DM), the outer flange was located in deep stroma (85%). 3 differentmaterials were tested: hydrophobic PMMA (n=5), hydrophilic HEMA–MMA(n=5) and HEMA–NVP (n=5), with a water content of 34%and 75%, respectively. The corneal surface was covered witha conjunctiva–Tenon flap. Central flap trephination wasperformed after 63 ± 7 days. Degree of DM vascularisationand scarring was assessed after flap opening and weekly thereafter.Results: In all 15 consecutive cases implantation of the sDSCcould be completed successfully without perforation of DM. Repairof the conjunctival flap had to be performed in 5 rabbits. Fourmonths after surgery, 3 of the 5 corneas (60%) with a PMMA implantand 3 of the 5 (60%) with a HEMA–NVP75 implant retainedcentral transparency, the others had developed neovascularisationin the DM–KPro optic interface. All corneas (100%) thatreceived an sDSC made of HEMA–MMA34 displayed a completeclear DM without any vessels or scarring. DM was found firmlyattached to the posterior surface of the optic.Conclusions: Implantation of a non–perforating syntheticcornea on top of an exposed DM is feasible. Regarding maintenanceof DM transparency HEMA–MMA34 showed the most promisingresults. As opening of the anterior chamber is not required,a lamellar supraDescemetic Synthetic Cornea would theoreticallyhave less risks and complications than a penetrating KPro.